1. Field of the Invention
The present invention relates to a video tape reproducing apparatus having an integrated circuit in which an amplifier for amplifying an output of an audio head and an amplifier for amplifying an output of a control head are integrated with each other.
2. Description of the Related Art
A fixed type audio head for reproducing an audio signal recorded on a video tape and a control head for reproducing a control signal are integrated into one head in response to requirements for easiness of attachment and reduction of size. FIG. 4 shows an example of the integrated head. In FIG. 4, reference numeral 3 designates a control head; and 4, an audio head. Both a control signal reproduced by the control head 3 and an audio signal reproduced by the audio head 4 are led to a signal processing board 52 through a connector 51. The audio signal led to the board 52 through the connector 51 is led to an integrated circuit 55 containing an audio signal amplifier so as to be amplified therein. The control signal led to the board 52 through the connector 51 is led to an integrated circuit 56 containing a control signal amplifier and the like so as to be processed therein.
In the aforementioned configuration, however, a problem arises as follows. That is, the integrated circuit 55 containing the audio signal amplifier is formed as a multifunctional integrated circuit containing luminance signal and chrominance signal processing circuits and the like. Further, the integrated circuit 56 containing the control signal amplifier and the like is similarly formed also as a multifunctional integrated circuit in which a microcomputer for controlling the operation of the apparatus and the like are integrated. Accordingly, each of the integrated circuits 55 and 56 has a large number of pins, so that a very large number of patterns are necessarily arranged in the periphery of each of the integrated circuits 55 and 56. Further, it is very difficult, also in terms of the arrangement of other signal processing circuits, to form such patterns even though the integrated circuits 55 and 56 are intended to be provided in proximity to each other. Accordingly, the integrated circuits 55 and 56 must be provided so as to be far from each other. As a result, when the integrated circuit 55 is arranged in proximity to the connector 51 to give preference to shortening of audio signal patterns, the integrated circuit 56 is provided necessarily so as to be far from the connector 51. Accordingly, patterns 57 and 58 for leading the control signal to the integrated circuit 56 become necessarily long-path patterns.
On the other hand, both the audio signal reproduced by the audio head 4 and the control signal reproduced by the control head 3 are micro-level signals in which the signal-to-noise ratio (S/N) is apt to be worsened by the influence of ambient noise. The patterns for leading the control signal to the integrated circuit 56, however, must be provided as long patterns in terms of the arrangement of the integrated circuit 56. Therefore, the hot-level pattern 57 and the cold-level pattern 58 are arranged adjacently to each other as the patterns for the control signal to thereby eliminate the influence of common-mode noise. However, even in the case where such pattern lines making a pair are used, the S/N of the control signal is apt to be worsened because the patterns are long. Accordingly, consideration, for example, of arranging the patterns 57 and 58 away from digital pulse transmission patterns is required. This is a large limitation on formation of patterns.
The present invention has been made to solve the aforementioned problem and an object thereof is to provide a video tape reproducing apparatus in which the patterns for micro-level signals can be formed easily.
In order to achieve the above object, according to the present invention, there is provided a video tape reproducing apparatus comprising: a fixed audio head for reproducing an audio signal recorded on a video tape; a fixed control head for reproducing a control signal recorded on the video tape; and an integrated circuit in which an audio signal amplifier for amplifying the audio signal reproduced by the audio head, and a control signal amplifier for amplifying the control signal reproduced by the control head are integrated with each other.
Thus, by simply providing the connection between the audio head and a board and the connection between the control head and the board in proximity to one integrated circuit, both the pattern for the audio signal from the audio head and the pattern for the control signal from the control head become short necessarily. As a result, both the patterns are substantially free from the influence of ambient noise.